Work clamp for use on a drill press



May 5, 1959' C. A. SCHUMACHER WORK CLAMP FOR USE ON A DRILL PRESS FiledMay 24, 1956 INVENTOR.

BY WWW 3m Clarence A. Schumacher United States atent WORK CLAMP FOR USEON A DRILL PRESS Clarence A. Schumacher, Aurora, Colo.

Application May 24, 1956, Serial No. 587,137

3 Claims. (Cl. 77-63) The present invention relates to certain new anduseful improvements in a clamp which is expressly, but not necessarily,appropriately designed and constructed for use in securely positioningand holding work on a drill press table for drilling requirements.

In carrying out a preferred and therefore specific embodiment of theconcept a practical and reliable clamp has been evolved and produced,one which facilitates placing, clamping and holding the work on thedrill press table during the drilling stage and may be expediently andrapidly released so that when the drilling operation has been completedthe clamp, usually employed in a group of clamps may be quickly detachedand placed aside for the next operational step and so that the drilledwork piece may be likewise removed from the press.

Stated along other and similar lines, the improved clamp has beendesigned with the idea in the mind of saving man hours and speeding upproduction in jig and drill press departments and any place where theuse of clamps and clamping requirements are involved, for instance, inairplane factories and the like.

With a view toward achieving the desired end results with efliciency andlooking toward satisfactory accomplishment and production of a highlydesirable clamp, advantageous over C-clamps, a triple-part constructionis employed. A principal part comprises an L-shaped body member the longlimb of which is provided with a toothed rack on which slidable orrelatively movable jaw means is shiftable, is provided with a pivotedgrip, and a leveroperated cam arrangement for more satisfactorilyapplying and removing the grip. On the short arm there is complementaljaw means which, more specifically, functions as a sort of an anvil andis bound, when in use, against the underside of the drill press table.

Other objects, features and advantages will become more readily apparentfrom the following description and the accompanying sheet ofillustrative, but not necessarily restrictive, drawings.

In the drawings, wherein like numerals are employed to designate likeparts throughout the view:

Figure l is a fragmentray elevational view of a drill press showing apiece of work on the work table illustrating two of the speciallydevised improved work clamps and how they are preferably used;

Figure 2 is an edge elevation on a slightly enlarged scale of theimproved clamp;

Figure 3 is a side view on approximately the same scale but withportions broken away to disclose the details and arrangement thereof;

Figure 4 is a section on the vertical line 4--4 of Figure 3; and

Figure 5 is a fragmentary detail view showing the cam construction in aposition slightly different from that appearing in Figure 3.

Although the clamp was devised with the thought in mind that it is ineffect a vise of a readily applicable and removable type for a drillpress table, it will be evident that the novelty resides structurallyand functionally in the clamp regardless of its purpose and use. In Fig.1, to assist in presenting the invention, the numeral 6 designates,generally speaking, a stand of a drill press wherein the drill isdenoted at 8 and the drill press table at 10. The work piece 12 is heldpartly in its intended drilling position by way of upstanding adjustableedge-engaging lugs or pins 14. Any number of these special clamps wouldbe used to assist in firmly binding the work piece on the table fordrilling steps. Each clamp is the same and the description of one willsuffice for all. To this end, and as seen in Fig. 3 the L-shaped bodymember is denoted as an entity by the numeral 16. It is a sturdy metalpart comprising a long limb or arm 18 one edge of which is formed withteeth to provide a rack 26 The short arm 20 carries the readilyapplicable and removable jaw unit 24 which is also herein described asan anvil. The anvil portion 26 is constructed so that it is bound firmlybeneath the work table. There is a loop portion 28 which slides on theshort arm and is held in place by a setscrew 30.

The novelly constructed shiftable jaw means is denoted by the numeral32. This is characterized by a substantially U-shaped member having abight portion 34 carrying a setscrew 36 engaging the edge 38 of the longarm 18. The arm portions 40 straddle and extend well beyond the toothedrack and bridging and rigidly secured to the upper edges of theintermediate portions of the arms there is a dog 42 engaging the rackteeth. Thus the dog and setscrew make it possible to adjust thisU-shaped member up and down to its primary or initially set position.The hingedly and pivotally mounted jaw or grip is denoted by the numeral44 and this is provided with flanges 46 which straddle and are hingedlymounted as at 48 on an an ear 50 of the quick-adjusting actuator 52.This is confined for operation between the outer ends of the arms 40 andit is of elongate or ovate form and is hingedly mounted for limitedswinging movement as at 54. This member 52 has a central substantiallycircular opening or hole 56 therein which serves to accommodate acircular cam 58. An edge portion 60 of the hole, as best seen in Fig. 5,is offset to provide a stop shoulder so that the bodily travelled motionof the cam is limited when it comes against the shoulder, making itnecessary to turn the cam first in one direction and then in the otherby way of the lever 62. The lever 62 has a crank portion 64 whichextends eccentrically through and operates the cam in a generallyobvious manner.

In using the clamping devices they are assembled on the drill presstable in the manner generally illustrated in Fig. 1. The drill presstable is one which has a marginal flange or skirt and obviously theanvil member or jaw 24 is shifted and held by the setscrew so that thejaw means 32 above it will be in readiness to be adjusted toward andfrom the work piece. The primary adjustment is made by way of thesetscrew 36 and the U-shaped member 32 with its dog 42 engaging the rackteeth 20. The planned adjustment is made by operating the lever actuatedcam and the pivoted block-like member 52 which carries theself-levelling jaw face or grip 44.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly, all suitable modifications and equivalentsmay be resorted to, falling within the scope of the in vention asclaimed.

What is claimed as new is as follows:

1. A clamp comprising a substantially L-shaped body member having longand short arms, said long arm being provided with rack teeth, an anvilmember slidably and operably mounted on said short arm and provided withadjustable retaining means engageable with the short arm permitting theanvil member to be positioned and retained where desired, a U-shapedmember slidably mounted on the long arm with its arm portions straddlingthe long arm and provided with a fixed dog adjustably engageable withthe rack teeth, the arms of said U-shaped member projecting Well beyondsaid teeth, a block-like member operatively confined between said armsand pivotally mounted at one end between the arms, provided intermediateits ends with an opening, a jaw member pivotally connected to the otherend of said block-like member, a cam confined for operation in theopening in said blocklike member, a lever having a crank at one end,said crank extending through bearings provided therefor in the arms ofsaid U-shaped member and being connected with said cam whereby the cammay be adjusted.

2. A work clamp for use on and in conjunction with a drill presscomprising a substantially L-shaped body member having long and shortarms, said long arm being provided along one longitudinal edge withfinely graduated transverse rack teeth, the other edge being smooth, ananvil member having a loop portion slidably and operatively mounted onsaid short arm and provided with adjustable retaining means engageblewith the edge of the short arm and permitting the anvil to be positionedand be retained wherever necessary or desired, the anvil properprojecting at right angles beyond said short arm and being disposednormally in spaced parallelism in relation to the rack teeth, a U-shapedslide having a bight portion and arm portions, said bight portion beingopposed to the edge of the long arm opposite to the edge with the rackteeth and said bight portion having a setscrew engageable with thecooperating edge, said arms having free end portions straddling the longarm and projecting beyond the rack teeth and terminating for cooperativerelationship with the anvil, a rigid dog bridging and rigidly secured tothe upper edge portions of the intermediate portions of the arms, saiddog being in plane above said upper edges and positioned for cooperationwith the rack teeth so that the dog and setscrew make it possible toadjust the U-shaped slide and to hold it in its initially set position,a quickadjusting actuator device confined and hingedly mounted betweenthe outer end portions of said arms, a jaw cooperable with said'dog andhingedly connected with a free swingable end portion of said actuatordevice, and crankoperated cam and slot means cooperating with theactuator device and said arm and serving to tighten and loosen said jawwhen cooperating with the workpiece interposed between the jaw andanvil.

3. A work clamp for use on and in conjunction with a drill presscomprising a substantially L-shaped body member having long and shortarms,'said long arm being provided along one longitudinal edge with afinely graduated transverse rack teeth, the other edge being smooth, ananvil member having a loop portion slidably and operatively mounted onsaid short arm and provided with adjustable retaining means engageablewith the edge of the short arm and permitting the anvil to be positionedand be retained wherever necessary or desired, the anvil properprojecting at right angles beyond said short arm and being disposednormally in spaced parallelism in relation to the rack teeth, a U-shapedslide having a bight portion and arms, said bight portion being opposedto the edge of the long arm opposite to the edge with the rack teeth andsaid bight portion having a setscrew engageable With the cooperatingedge, said arms having free end portions straddling the long arm andprojecting beyond the rack teeth and terminating for cooperativerelationship with the anvil, a rigid dog bridging and rigidly secured tothe upper edge portions of the intermediate portions of the arms, saiddog being in plane above said upper edges and positioned for cooperationwith the rack teeth so that the dog and setscrew make it possible toadjust the U- shaped slide and to hold it in its initially set position,a,

quick-adjusting actuator device confined and hingedly mounted betweenthe outer end portions of said arms, a jaw cooperable with said dog andhingedly connected with a free swingable end portion of said actuatordevice, said actuator device being of elongated form, the centralportion thereof being provided with a substantially circular hole, a camconfined for operation in said hole and located between the adjacentinner surfaces of said arms, said arms being provided with bearings, anda handle having a crank mounted for rotation in said bearings, saidcrank extending 'eccentrically through and being rigidly joined to saidcam in a manner to rotate and thus operate the cam. 7

References Cited in the file of this patent UNITED STATES PATENTS237,431 Colt Feb. 8, 1881 FOREIGN PATENTS 7,676 Great Britain AD. 189510,312 Switzerland May 16, 1895

